?~Velocity Loss From A 6-Inch Barrel, To A 4-Inch Barrel>? [Archive] - Glock Talk


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08-27-2012, 12:09
Talking about a "Magsafe" Pre-Fragmented round from a S&W m-25.

Rated @ 1,700fps from a 6-inch tube. I was thinking at least 1,300fps, from a 4-incher, and able to frag as claimed.

:dunno: Most of my testing was done years ago, with 9mm loads. Not sure what to tell someone today, with a big-bor blaster.


08-27-2012, 12:16
You generally lose 100-110fps per inch from whatbive seen. So 220ish......not enough to greatly matter. 300-400 start worrying ;)

sent from my phone. i am not responsible for spelling errors, jumbled words, spanglish or anything else. blame a touch screen and autocorrect :)

08-27-2012, 12:47
If the factory rated the round @ 1700fps from a 6" barrel you probably will not get that. Most "factory" ammo will come in lower than advertised.

08-27-2012, 17:07
Lighter weight and higher speeds will loose more velocity in shorter barrels than heavier/slower rounds. Since the Magsafe rounds are extremely light and fast, the difference should be pretty large. In general, you really can't guestimate velocity and then when you throw in the characteristics of the Magsafe rounds, it really becomes like trying to figure out how many jelly beans are in a jar.

Your best bet is to have a pool, like a football pool, where people can buy boxes. Then run them over a chronograph and see who wins. What will the prize be?